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Convection in 3He–superfluid-4He mixtures. Part 2. A survey of instabilities

Published online by Cambridge University Press:  26 April 2006

Guy Metcalfe
Affiliation:
Division of Building, Construction and Engineering, CSIRO, Highett 3190, Australia
R. P. Behringer
Affiliation:
Duke University Department of Physics and Center for Nonlinear and Complex Systems, Durham, NC 27708, USA

Abstract

Dilute mixtures of 3He in superfluid 4He have Prandtl numbers easily tunable between those of liquid metals and water: 0.04 < Pr < 2. Moreover, superfluid mixture convection is closely analogous to classical Rayleigh–Bénard convection, i.e. superfluid mixtures convect as if they were classical, single-component fluids. This work has two goals. The first, accomplished in Part 1, is to experimentally validate the superfluid mixture convection analogue to Rayleigh–Bénard convection.

With superfluid effects understood and under control, the second goal is to identify and characterize time-dependence and chaos and to discover new dynamical behaviour in strongly nonlinear convective flows. In this paper, Part 2, we exploit the unique Pr range of superfluid mixtures and the variable aspect ratio (Γ) capabilities of our experiment to survey convective instabilities in the broad, and heretofore largely unexplored, parameter space 0.12 < Pr < 1.4 and 2 < Γ < 95. Within this large parameter space, we have focused on small to moderate Γ and Pr and on large Γ with Pr ≈ 1. The novel behaviour uncovered in the survey includes the following. Changing attractors: at Γ = 6.0 and Pr = 0.3, we observe intermittent bursting destabilizing a fully developed chaotic state. Above the onset of bursting the average length of a burst-free interval and the average length of a burst vary as power laws. At Γ = 4.25 and Pr = 0.12 we observe a particularly novel reversible switching transition involving two chaotic attractors. Instability competition: near the codimension-2 point at the crossing of the skewed-varicose and oscillatory instabilities we find that the effects of instability competition greatly increase the complexity and multiplicity of states. A heat-pulse method allows selection of the active state. Decreasing Γ suppresses the available complexity. Superfluid turbulence: we find that the large-amplitude noisy states, previously believed due to superfluid turbulence, are confined to small values of Γ and Pr and are not consistent with superfluid turbulence. Changing instabilities: at Pr = 0.19 a wavevector detuning changes the type of secondary instability from oscillatory to saddle-node, with an unusual 3/4 exponent time scaling. Very large Γ: at Pr = 1.3 for Γ increasing from 44 to 90, we observe the onset of convection changing from ordered and stationary to disordered and time-dependent. At the beginning of the crossover there are hysteretic transitions to coherent oscillations close to the onset of convection. By the end of the crossover convection is time-dependent and irregular at onset with the fluctuation amplitude correlated with the mean Nusselt number.

Type
Research Article
Copyright
© 1996 Cambridge University Press

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References

Ahlers, G. & Behringer, R. P. 1978 The Rayleigh-Bénard instability and the evolution of turbulence. Supp. Prog. Theor. Phys. 64, 186201.Google Scholar
Aubry, N., Holmes, P., Lumley, J. L. & Stone, E. 1988 The dynamics of coherent structures in the wall region of a turbulent boundary layer. J. Fluid Mech. 192, 115173.Google Scholar
Behringer, R. P. 1985 Rayleigh-Bénard convection and turbulence in liquid helium. Rev. Mod. Phys. 57, 657687.Google Scholar
Bergé, P., Dubois, M., Manneville, P. & Pomeau, Y. 1980 Intermittency in Rayleigh–Bénard convection. J. Phys. (Paris) Lett. 41, L341345.Google Scholar
Bodenschatz, E., Bruyn, J. R. DE, Ahlers, G. & Cannell, D. S. 1991 Transition between patterns in thermal convection. Phys. Rev. Lett. 67, 30783081.Google Scholar
Brand, H. R., Hohenberg, P. C. & Steinberg, V. 1984 Codimension-2 bifurcations for convection in binary fluid mixtures. Phys. Rev. A 30, 25482561.Google Scholar
Busse, B. H. 1981 Transition to turbulence in Rayleigh-Bénard convection. In Hydrodynamic Instabilities and the Transition to Turbulence (ed. H. L. Swinney & J. P. Gollub), pp. 97137. Springer.
Chandrasekhar, S. 1961 Hydrodynamic and Hydromagnetic Stability. Dover.
Charlson, G. S. & Sani, R. L. 1975 Finite amplitude axisymmetric thermoconvective flows in a bounded cylindrical layer of fluid. J. Fluid Mech. 71, 209229.Google Scholar
Chiffaudel, A., Fauve, S. & Perrin, B. 1987 Viscous and inertial convection at low Prandtl number; Experimental study. Europhys. Lett. 4, 555560.Google Scholar
Chiffaudel, A., Perrin, B. & Fauve, S. 1989 Spatiotemporal dynamics of oscillatory convection at low Prandtl number: Waves and defects. Phys. Rev. A 39, 27612764.Google Scholar
Clever, R. M. & Busse, F. H. 1974 Transition to time-dependent convection. J. Fluid Mech. 65, 625645.Google Scholar
Croquette, V. 1989 Convective pattern dynamics at low Prandtl number: Part I. Contem. Phys. 30, 113133.Google Scholar
Deissler, R. J., Ecke, R. E. & Haucke, H. 1987 Universal scaling and transient behaviour of temporal modes near a Hopf bifurcation. Phys. Rev. A 36, 43904401.Google Scholar
Dubois, M., Rubio, M. A. & Bergé, P. 1983 Experimental evidence of intermittencies associated with a subharmonic bifurcation. Phys. Rev. Lett. 51, 14461449.Google Scholar
Ecke, R. E., Haucke, H. & Wheatley, J. C. 1987 Convectively driven superfluid turbulence in dilute solutions of 3He-superfluid-4He. Can. J. Phys. 65, 13221327.Google Scholar
Gollub, J. P. & Benson, S. V. 1980 Many routes to turbulent convection. J. Fluid Mech. 100, 449470.Google Scholar
Grebogi, C., Ott, E. & Yorke, J. A. 1983 Crises, sudden changes in chaotic attractors and transient chaos. Physica D7, 181200.Google Scholar
Grebogi, C., Ott, E. Romeiras, F. & Yorke, J. A. 1987 Critical exponents for crisis-induced intermittency. Phys. Rev. A 36, 53655380.Google Scholar
Guckenheimer, J. & Holmes, P. 1983 Nonlinear Oscillations, Dynamical Systems, and Bifurcations of Vector Fields. Springer.
Haucke, H., Ecke, R. E., Maeno, Y. & Wheatley, J. C. 1984 Noise-induced intermittency in a convecting dilute solution of 3He in superfluid 4He. Phy. Rev. Lett. 53, 20902093.Google Scholar
Haucke, H., Maeno, Y., Warkentin, P. & Wheatley, J. 1980 Time-dependent thermal convection in dilute solutions of 3He in superfluid 4He. J. Low Temp. Phys. 44, 505533.Google Scholar
Holmes, P. 1990 Can dynamical systems approach turbulence? In Whither Turbulence? Turbulence at the Crossroads (ed. J. L. Lumley). Springer.
Kennel, M. B., Brown, R. & Abarbenel, H. D. I. 1992 Determining embedding dimension for phase-space reconstruction using a geometrical construction. Phys. Rev. A 45, 34033411.Google Scholar
Libchaber, A., Fauve, S. & Laroche, C. 1983 Two-parameter study of the routes to chaos. Physica 7D, 7384.Google Scholar
Mainieri, R., Sullivan, T. S. & Ecke, R. E. 1989 Two-parameter study of the quasiperiodic route to chaos in convecting 3He-superfluid-4He mixtures. Phys. Rev. Lett. 63, 23572360.Google Scholar
Manneville, P. 1990 Dissipative Structures and Weak Turbulence. Academic Press.
Metcalfe, G. 1991 Using superfluid mixtures to probe convective instabilities. PhD thesis, Duke University.
Metcalfe, G. & Behringer, R. P. 1996 Convection in 3He–superfluid-4He mixtures. Part 1. A Boussinesq analogue. J. Fluid Mech. 307, 269296.Google Scholar
Meyer, C. W., Ahlers, G. & Cannell, D. S. 1987 Initial stages of pattern formation in Rayleigh-Bénard convection. Phys. Rev. Lett. 59, 15771580.Google Scholar
Morris, S. W., Bodenschatz, E., Cannell, D. S. & Ahlers, G. 1993 Spiral defect chaos in large aspect ratio Rayleigh–Bénard convection. Phys. Rev. Lett. 71, 20262029.Google Scholar
Motsay, R. W., Anderson, K. E. & Behringer, R. P. 1988 The onset of convection and turbulence in rectangular layers of normal liquid 4He. J. Fluid Mech. 189, 263286.Google Scholar
Newell, A. C, Passot, T. & Souli, M. 1990 The phase diffusion and mean drift equations for convection at finite Rayleigh numbers in large containers. J. Fluid Mech. 220, 187252.Google Scholar
Pomeau, Y. & Manneville, P. 1980 Intermittent transition to turbulence in dissipative dynamical systems. Commun. Math. Phys. 74, 189197.Google Scholar
Rehberg, I. & Ahlers, G. 1985 Experimental observation of a codimension-two bifurcation in a binary fluid mixture. Phys. Rev. Lett. 55, 500503.Google Scholar
Stone, E. & Holmes, P. 1990 Random perturbations of heteroclinic attractors. SIAM J. Appl. Maths 50, 726743.Google Scholar
Sullivan, T. S. & Ahlers, G. 1988 Hopf bifurcation to convection near the codimension-two point in a 3He-4He mixture. Phys. Rev. Lett. 61, 7881.Google Scholar
Theiler, J. 1987 Efficient algorithm for estimating the correlation dimension from a set of discrete points. Phys. Rev. A 36, 44564462.Google Scholar